19 lines
484 B
TypeScript
19 lines
484 B
TypeScript
export class Random {
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// don't set the seed 0
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public constructor(public seed: number = 42) {}
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public get next(): number {
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// result is in [0, 1)
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this.seed = Math.imul(48271, this.seed);
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return ((2 ** 31 - 1) & this.seed) / 2 ** 31;
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}
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public choose<T>(list: Array<T>): T {
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return list[Math.floor(this.inInterval(0, list.length))];
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}
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public inInterval(aClosed: number, bOpen: number): number {
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return (bOpen - aClosed) * this.next + aClosed;
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}
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}
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